Electrical lead connectors



June 4, 1963 w, MILLER 3,092,430

ELECTRICAL LEAD CONNECTORS Filed Oct. 12, 1961 INVENTOR.

JOHN W. MILLER W a ATTORNEYS This invention relates to improved electrical connectors for use at the ends of electrical leads to connect various electrical devices together.

One type of conventional electrical lead connector comprises a casing structure having a plug portion for reception in any suitable receiving socket on a panel of an electrical device or in another lead connector. This type of connector is often referred to in the art as a banana plug connector since the plug portion is formed of resilient bowed strips, generally conforming to the shape of a banana.

In order to enable more than one lead to be connected to any one panel terminal or to any one other connector, the casing structure supporting the banana plug itself includes a socket so that another banana plug may be received therein. This additional banana plug in turn may include in its supporting casing a socket for reception of still another banana plug.

While electrical leads terminating in such type plugs are provided in varying lengths to facilitate connecting together various different electrical devices, there are many instances in which a proper length is not readily avail-able. It is common practice, therefore, to connect a pair of readily available electrical leads together by inserting the banana plug at the end of one lead through the corresponding socket formed in the casing for the banana plug at the end of another lead, thereby connecting the leads in series. In this manner, a desired length of electrical wire may be provided. A disadvantage, however, of connecting leads in this manner results from the exposure of various banana plugs between series connected leads. In case relatively high voltage exists on the leads, there is a shock hazard as Well as danger of inadvertent grounding because of the exposed portions of the connector plugs.

With the foregoing in mind, it is a primary object of this invention to provide an improved lead connector which has all the advantages of the present day banana plug type connectors and yet which may be connected to an identical lead connector at the end of an additional lead in such a manner as to cover completely the plug portions of the connectors to the end that hazards from shock, grounding, or short circuits are wholly eliminated.

Other objects of this invention are to provide improved electrical lead connectors meeting the foregoing object, which may be manufactured relatively economically, which require only minor modifications of present day connectors, and which do not increase materially the overall bulk or size of the connectors.

Briefly, these and other objects and advantages of this invention are attained by providing a casing having a banana plug type connecting portion extending from one end and also including a banana plug socket at the same end adjacent to the plug portion. The axis of the socket is parallel to the axis of the plug so that an identically constructed casing, plug, and socket on another lead may be simply rotated 180 degrees and connected to the first mentioned plug and socket structure in a manner such that both of the banana type plugs are completely covered and concealed.

The connectors themselves may include auxiliary socket openings for receiving other banana plugs in the same manner as is already provided on existing connectors.

A better understanding of the invention and its various features and advantages will be had by referring to one ates atcnt 'ice 2 embodiment thereof as illustrated in the accompanying drawings, in which:

FIGURE 1 illustrates conventional type electrical lead connectors;

FIGURE 2 illustrates similar connections as shown in FIGURE 1 employing the improved lead connectors of this invention; and,

FIGURE 3 is an enlarged cross section of the improved electrical lead connector.

Referring first to FIGURE 1, there is shown a conventional type electrical lead 1 0 terminating at one end in a conventional electrical connector 1'1 and at its other end in an identical connector 112. A second lead 13 terminating in a connector .14 is shown in electrical connection with the connector 12. The other end of the lead 13 shown at 15 may extend to some piece of electrical equipment or to a power source.

The three illustrated connectors, 11, 12, and 14, are all identical. As shown, the connector 12, for example, includes a casing from which a plug 16 of the banana type extends. Also provided is a transverse bore or opening 17 in the casing dimensioned to receive a banana plug from another connector.

Similarly, the connector 14 includes a banana type plug 18. In the particular electrical connections illustrated in FIGURE 1, the plug 18 is received within the bore 17 to connect the electrical lead wire :13 to the electrical lead wire 10.

In addition to the transverse bores such as illustrated at 17 and 19 for the connectors .12 and 14, each connector may also include a rear socket portion such as illustrated at 20 for the connector 14, also dimensioned to receive a banana plug.

As :an example of the purpose for connecting the various leads as illustrated in FIGURE 1, assume that it is desired to connect a 300' volt source to a terminal 21 on panel of an instrument and further assume that the electrical leads available are not of sufficient length. In this event, by connecting two of the leads such as 10 and 13 together as shown, a proper length is provided. On the other hand, it will be noted that with the connections as made, both the banana type plugs 16 for the connector 12 and 1-8 for the connector 14 are relatively exposed and thus present a shock hazard as well as being subject to inadvertent grounding. While it is possible to insert the banana plug 18 in the socket portion at the rear of the connector .12., the banana plug 16 of the connector 12 would still be exposed.

The foregoing problems are overcome in accordance with the present invention by providing connectors as illustrated in FIGURE 2 wherein a similar connection as described in FIGURE 1 is shown. In FIGURE 2, there is illustrated an electrical lead 22 terminating at one end in the improved connector 23 and at its other end in an identical connector 24. A second electrical lead 25 in turn terminates at one end in the improved connector 26 of this invention and may have its other end connected to the voltage source corresponding to the connection of the lead portion 15 shown in FIGURE .1. The various improved connectors 23, 24, and 26 are all identical and therefore description of one will suffice for all.

With particular reference to FIGURE 3, there is illustrated the connector 24 which comprises an insulated casing 27 housing a first tubular member 28. As shown, the tubular member 28 terminates at one end in a banana plug 29 and may include a transverse bore 30 corresponding to the openings 17 and 19 illustrated in the connectors 12 and 14 of FIGURE 1. Also included within the casing 24 is a second tubular member 31 terminating in an open end adjacent to the plug 29. This open end is dimensioned to receive a plug identical to the plug 29. The other end of the second tubular member 31 connects to the lead 22 as at 3-2. The first and second tubular members 28 and 31 are in side-by-side parallel relationship and in physical and electrical contact with each other as illustrated. The axis of the receiving socket of the second tubular member 31 is parallel to the longitudinal axis of the banana plug 29.

With the foregoing arrangement, it will be evident that a plug identical to the plug 24 may be rotated 180 degrees so that its plug member is received Within the second tubular member 31 and simultaneously its corre sponding second tubular member receives the plug 29 of the connector 24. The connecting relationship is illustrated by the two plugs 24 and 26 in FIGURE 2 wherein the plug portions and receiving second tubular members are illustrated in dotted lines.

,It will be immediately evident that an identical connection insofar as the electrical properties are concerned is effected by the connectors of FIGURE 2 as is achieved by the connectors of FIGURE 1. On the other hand, both of the banana type plug connectors are themselves completely covered, and there are no exposed conducting portions which may cause a shock hazard or inadvertently become grounded.

Moreover, each of the connectors as illustrated in FIGURES 2 and 3 include a transverse bore opening and rear socket for receiving additional plugs so that any two additional'connectors may be connected to any one of the connectors. Thus, all of the advantages of the connectors described in conjunction with FIGURE 1 are retained without the disadvantages accruing when the same are connected together.

From the foregoing description, it will be evident that the present invention has provided a greatly improved electrical lead connector wherein the primary objective is achieved without materially increasing the overall bulk of the connector itself.

What is claimed is: a

1. An electrical lead connector comprising: an insulating casing; first and second elongated tubular members electrically secured together in side-by-side parallel relationship within said casing, said first member terminating at one end in a plug and at its other end in an open socket dimensioned to receive a plug identical to said first mentioned plug, the end of said second tubular member adjacent said first mentioned plug being open and dimensioned to receive a plug identical to said first mentioned plug, the opposite end of said second tubular member being connected to said electrical lead whereby an additional lead connector identical to said first mentioned lead connector may have its plug received in the end of said second tubular member adjacent said first mentioned plug and simultaneously receive said first mentioned plug in the corresponding second tubular member of said additional lead connector, an additional plug being receivable in said open socket at said other end of said first tubular member.

2. An electrical lead connector according to claim 1, in which said casing includes a bore passing at right angles through said first tubular member and dimensioned to receive a further plug identical to said first mentioned plug, whereby more than two additional connectors may be connected to said first mentioned connector.

References Cited in the file of this patent UNITED STATES PATENTS 551,930 Greene Dec. 24, 1895 995,674 Hertzberg'et a1 June 20, 1911 1,421,017 Lundberg June 27, 1922 2,058,292 Benander Oct. 20, 1936 2,406,895 Olson Sept. 3, 1946 2,591,009 Riche Apr. 1, 195-2 2,591,437 Jun 2 Apr. 1, 1952 2,654,077 McLoad Sept. 29, 1953 2,738,477 Matthysse Mar. 13, 1956 FOREIGN PATENTS 248,616 Great Britain Mar. 11, 1926 

1. AN ELECTRICAL LEAD CONNECTOR COMPRISING: AN INSULATING CASING; FIRST AND SECOND ELONGATED TUBULAR MEMBERS ELECTRICALLY SECURED TOGETHER IN SIDE-BY-SIDE PARALLEL RELATIONSHIP WITHIN SAID CASING, SAID FIRST MEMBER TERMINATING AT ONE END IN A PLUG AND AT ITS OTHER END IN AN OPEN SOCKET DIMENSIONED TO RECEIVE A PLUG IDENTICAL TO SAID FIRST MENTIONED PLUG, THE END OF SAID SECOND TUBULAR MEMBER ADJACENT SAID FIRST MENTIONED PLUG BEING OPEN AND DIMENSIONED TO RECEIVE A PLUG IDENTICAL TO SAID FIRST MENTIONED PLUG, THE OPPOSITE END OF SAID SECOND TUBULAR MEMBER BEING CONNECTED TO SAID ELECTRICAL LEAD WHEREBY AN ADDITIONAL LEAD CONNECTOR IDENTICAL TO SAID FIRST MENTIONED LEAD CONNECTOR MAY HAVE ITS PLUG RECEIVED IN THE END OF SAID SECOND TUBULAR MEMBER ADJACENT SAID FIRST MENTIONED PLUG AND SIMULTANEOUSLY RECEIVE SAID FIRST MENTIONED PLUG IN THE CORRESPONDING SECOND TUBULAR MEMBER OF SAID ADDITIONAL LEAD CONNECTOR, AN ADDITIONAL PLUG BEING RECEIVABLE IN SAID OPEN SOCKET AT SAID OTHER END OF SAID FIRST TUBULAR MEMBER. 